While various types of combs that clear hair of strongly attached particles are known in the art, and particularly lice combs, the problem of foreign agents on human or animal hair has not yet been solved. The most important problem is that of nits (i.e. the eggs of human lice) for they are more strongly attached to hair.
In U.S. Pat. No. 4,612,945 there is described a comb that is useful to clear hair of lice and nits. This comb has teeth having a triangle-shaped cross section. The diameter of the teeth is tapered from the gripping ends to the leading ends, so that the distance between adjacent teeth is larger at the leading ends that close to the handle. The teeth are arranged with their longitudinal axes parallel to each other end on two different planes, with adjacent teeth staggered between both planes. With this design a scissors effect is achieved to detach lice and nits. This comb, however, has a few drawbacks. Its teeth have a limited length, whereby not always is it possible to reach the bottom of the hair. The distance between the leading ends of the teeth is substantially large, so the efficiency against lice and particularly against their eggs, is significantly reduced. In addition, teeth are triangle-shaped with sharp edges and thus they tend to damage hair, which is a totally undesired effect.
In U.S. Pat. No. 4,671,303 there is disclosed a nit comb and a method of manufacturing the same. The comb includes a plurality of metal teeth , which are mounted on a handle, with a distance between the teeth of about 100 .mu.m to 120 .mu.m. Each tooth is provided with an elongated groove that matches an elongated interconnection member in the handle, to insure the teeth are held parallel to each other both during manufacturing and in use. The teeth are of a convenient length, i.e. there is a portion of each tooth that protrudes from the handle and can be used to comb the hair, of approximately 9 mm, and the ends are hook-shaped to aid in removing lice and nits from de hair. In many instances the reduced effective length is not suitable for the comb to reach the base of the hair. Despite the particular shape of the tips of the teeth, the comb lacks the required efficiency to remove the particles that remain strongly attached to the hair, such as nits, because the distance between teeth is to big and the surface of the teeth is smooth, therefore leaving most of the eggs ungrasped.